Scientific name:
Betta splendens
Note: The proper pronunciation of betta is “bet-tah” and not “bay-tah.”
Family Name:
Osphronemidae (Gourami Family)
Common name:
Betta, Siamese Fighting Fish
Average Adult Fish Size:
3 inches (7.6 cm)
Place of Origin and Description:
In the wild, nature selects for shorter fins enabling faster more agile movement, and duller shades of brown, grey, and green; colors which blend in with the natural surroundings. In Siam (now known as Thailand), bettas were primarily bred for bravery, not show, and while color varieties were selected for, long flowing fins were not. Wild bettas usually only show brighter colors when agitated and/or during mating season, whereas the bettas we see in aquariums today are bred for their long flowing fin shapes and vibrant colorations. Bettas are categorized according to fin types, patterns, and colors.
There are several tail fin shapes; the most common being the “veil tail’. Other shapes include:
• comb tail
• crown tail
• delta
• dumbo ear (although not a tail shape)
• super delta
• double tail
• feather tail
• half moon
• over half moon
• half sun
• plakat
• round tail
• rose tail
• short-finned fighting-style tail
• spade tail
Some pattern types include:
• Bi-Colored
• Butterfly
• Cambodian
• Dragon
• Marble
• Mask
• Multicolored
• Piebald
• Solid
• Wild Type
Some colorations include:
• Albino
• Black
• Blue / Steel Blue / Royal Blue
• Clear / Cellophane
• Chocolate
• Copper
• Green
• Mustard Gas
• Opaque / Pastels
• Orange
• Orange Dalmatian
• Purple / Violet
• Red
• Turquoise
• Wild-Type
• Yellow & Pineapple
Behavior:
In the wild, bettas live rather peacefully together, rarely getting aggressive unless it is breeding season. But because of selective breeding originating in Thailand where the fish are traditionally pitted against each other for sport, which is now illegal, aquarium-bred bettas can be very aggressive! Bettas are highly territorial. Males will attack and kill each other.
Although, some people like to keep two aquariums next to each other with an opaque divider between them, each aquarium housing one male. From time to time, to demonstrate the aggression displays of the males, the divider is removed for a short time. This is an interesting and safe (for the fish of course) way to observe male body posturing, and may also help to reduce pent-up stress.
Female bettas are sometimes kept together in the same aquarium. But they can be territorial as well. They may attack each other if kept in too small an aquarium or in an aquarium with less than optimal conditions. It is not recommended for beginners to keep more than one female betta in an aquarium.
Keeping a male and a female together should only be done temporarily for breeding purposes. This should always be supervised, as one may attack and try to kill the other. In some cases it isn’t always the male that is the aggressor.
Minimum Recommended Aquarium Size:
5 gallons
You often see bettas in pet stores being kept in small glass vases devoid of any place to hide. While it is true that one betta can survive for a time in quite a small enclosure, let’s consider a few things as to why this aquarium size is better.
Even though there is talk of bettas preferring to live in mud puddles and other small tight spaces, in the wild they actually live in very large bodies of water with access to moderate currents.
While there are many betta tanks being marketed as stackable and ideal for bettas, it is understood that those little betta cups lined up in pet stores are meant only to keep them separate within the limited space of the pet store. That said, most bettas sell quickly and are only present for a short time in those small containers.
The 1:1 Rule: for small fish, the absolute minimal aquarium size should be no less than 1 gallon per 1 inch of fish.
Also, keep in mind that an aquarium’s gallon size holds that much water when empty. Adding gravel, plants, a heater, thermometer, filter, etc. will reduce the amount of water the aquarium can hold. So, a 5 gallon aquarium will likely actually hold 3.5 gallons of water, cutting it close to the 1:1 Rule and the adult size of the betta.
This minimum aquarium size rule is based on the fact that fish are constantly converting food to waste. The ammonia and nitrate fish produce builds up very fast in smaller aquariums, thus the need for frequent water changes to maintain a stress-free environment. And while it is true that bettas, and many other fish for that matter, can survive in smaller tanks, provided the work to keep the water quality high is done… the truth is that bettas enjoy living in larger spaces… just like all other fish and living beings. Surviving, when it comes down to it, is not the same thing as thriving! For more info, read the article Aquarium Size and Basic Water Quality Setup.
Another argument for a larger betta aquarium size is that they are curious fish and enjoy having the option of exploring their environments, as well as being able to hide alone in uncontested cozy areas.
As previously stated, a betta aquarium should only ever hold 1 male. And so, if the betta species is the only species you are interested in, the 1:1 Rule need be greatly considered, as there are other factors.
Water quality is what matters. Happy Fish is a big advocate of that aquarium requirement. Every aquarium needs a filter to maintain high water quality. Herein lies a problem with most minimum betta aquarium size recommendations:
1. Filter pumps create excessive flow.
2. Bettas, while enjoying some very low flow, need ample area that is still. This area needs to be at the left or right of the aquarium, not the top or bottom.
3. Because bettas enjoy limited water flow, there will be less dissolved oxygen in the water for them to breathe. While it is true that adult bettas have a limited capacity to breathe atmospheric oxygen by way of an accessory breathing organ known as the ‘labyrinth’, they prefer gill respiration. This is one of the reasons to add lots of live plants to a betta aquarium. Live plants increase dissolved oxygen levels, and most do well in slow flowing water. In addition, bettas need lots of live plants to hide among to rest.
Juggling these 3 factors in a very small aquarium is difficult. Although it is relatively easy in a 5 gallon aquarium with a pump of which has an adjustable flow rate, it’s even easier in a 10 gallon. For more info, read Aquarium Size and Basic Water Quality Setup.
Temperature:
Widest range = 73 to 86 °F (23 to 30 °C)
Optimal range = 78 to 80 °F (25.6 to 26.7 °C)
A lower than optimal temperature is stressful, which can cause susceptibility to disease such as Ich (linked to Ich article), and higher than optimal shortens lifespan by increasing the aging process.
pH:
6.5 to 7.1
Tank Setup and Water Flow:
As stated above, in Minimum Recommended Aquarium Size. It is important the aquarium is covered to prevent the betta from jumping out.
Diet:
Carnivorous; use a high quality fish food specially made for bettas as the base diet. The occasional feeding of live food such as bloodworms, brine shrimp, daphnia, and mosquito larvae is recommended. Take care when feeding, as bettas have very small stomachs, about the size of one of their eyes, and so are easy to overfeed.
Sexing:
Males typically have much longer fins and are much more brightly colored than females which are typically greyish with subtle color variations. The fin difference is especially obvious when looking at the ventral fins. Females have an egg spot behind the ventral fins, whereas males do not.
Basic Breeding Info:
The male will build a bubble nest somewhere at the surface of the water, usually in a still corner of the aquarium. If he is not doing this already, then a slight raise in temperature and/or a little more food, without overfeeding, might induce his mating instinct.
When he is done building his nest, put a well-fed female into the aquarium. More advanced breeders can try more than one female at a time, but doing so increases the chances of aggressiveness. This is a suspenseful time, there may be violence rather than love, so maintain consistent observation! If all goes well, the male will entice the female to get under the nest with him. They exhibit mating behaviors and she will release her eggs as he fertilizes the eggs by releasing sperm.
The female then sinks down as though exhausted while the male picks up the eggs and puts them into the bubble nest. Any eggs not placed in a bubble will be eaten when she recovers. They will repeat this ritual until she has no more eggs, at which point he will chase her away from the nest. This is the time to remove her from the aquarium.
While the eggs are incubating and hatching, the male will guard them, and will continue to do so until they are swimming. At that point he will eat them so separate him from them into another aquarium.
The newly hatched fish are very small. In the wild they eat infusioria which is a collective term for minute aquatic creatures such as ciliates, euglenoids, protozoa, small invertebrates, and unicellular algae. Some of these will exist in any aquarium, but the hatchlings need an abundance of them to grow. Having live plants in the aquarium will increase the numbers of infusoria. Betta hatchlings might not be too keen on eating dry foods, even finely powdered ones, but they will readily eat anything alive that will fit in their mouths.
If you succeed in feeding them, they will grow. Soon they will be big enough to eat larger foods. At all stages, bettas benefit from some live food of suitable size.
At around 6 weeks old, the betta’s accessory breathing organ; the ‘labyrinth’ starts working. At this stage it will be necessary to have a small stream of air from an air stone to break up any surface film because the hatchlings might not be strong enough to penetrate this layer to get air.
The males and female hatchlings are normally separated as soon as they can be distinguished, with each male going into a separate aquarium.
Potential Health Issues:
Sometimes, a betta’s tail fin can get damaged for various reasons. A betta’s damaged tail fin is because of poor water quality or physical injury. Physical injury is not a disease and should not be confused with fin/tail rot. Rule out infection through correct diagnosis.
Poor water quality can contribute to infection but is not the only possible concern. Poor water quality might also contribute to aggressiveness in tankmates or self biting. Always take the appropriate steps to establish and maintain high water quality.
If the damage is physical injury, the possible causes need to be ruled out. This type of damage is caused by one of three things:
1. aquarium decor and setup
2. other fish biting
3. self-biting
Everything in the aquarium that the betta can touch needs to be soft and non-damaging. This includes making sure there are no abrasive, hard, pointy, or sharp objects (rocks, wood, plants); and also that the filter suction is low enough that it can’t cause damage.
If aquarium decor and setup are good, observation will be necessary to determine if the aggressor is a tankmate or if the betta is biting himself.
If it is an aggressive tank mate, separating the fish into two different aquariums will of course solve that problem. Although, if the aggressor is a schooling species known to be generally peaceful, school numbers may be too low and adding the recommended number of individuals may correct the behavior. For example, see Ember Tetras (linked)
If the damage is self-inflicted, the reasons can be many and may include:
• hunger
• stress (common in newly arrived bettas that were shipped and kept in dark containers for a long time)
• boredom
• pent-up aggression
• attempts to rid its fins of bacteria or fungus
• genetics
With regards to self-infliction, other than making sure the betta is sufficiently fed, a few changes may need to be made. Here are some things to try:
• Moving the aquarium to a new location, for example out of direct sunlight.
• Decrease the lighting, even if this means replacing plants that require brighter light with those that require lower light.
• If the aquarium is large enough, add one of more peaceful tankmates to relieve boredom. See Compatibility, below.
• Add a ping-pong ball for the betta to play with.
• Add a mirror somewhere the betta can go to relieve pent-up aggression against the mirror instead of its own fins. The mirror should be somewhere away from his nest and slightly concealed, so he needs to actively seek it out. This should be a temporary solution only.
• If all else fails, consider medicating with an antibacterial and antifungal betta fish infection and fungus remedy such as Bettafix.
After the self-biting has stopped, the fins will grow back to their full splendor!
Compatibility:
Bettas do not require the presence of any other fish. They are not a schooling or otherwise needfully communal species. They are perfectly fine living alone in their own tank. But that does not mean that aquarists can’t keep a betta with other fish. This does not mean that a betta would rather not have tankmates. Betta compatibility with other fish, and vice versa, depends largely on species temperament, and also on fish and aquarium size.
In tanks with plenty of room, bettas are generally non-aggressive, except towards members of their own species! An exception to this might be towards guppies or other species with long flowing tails that can be mistaken for male bettas. In large tanks, one betta can be successfully kept with other peaceful fish species of similar size or slightly smaller. However, fish that are too small risk being hunted, fin-nipped, and/or eaten by the betta.
Basic Statistics on a few species compatible with bettas:
Cory Catfish (Genus: Corydoras)
Size: 2.5 inches
Minimum Number: 2+ shoaling, 6+ schooling
Minimum Aquarium Size: 10 gallons or 1:1 rule, whichever is greater.
Temperature: 72 to 78 °F (22.2 to 25.6 °C)
pH: 7.0 to 7.8
Setup Specifics: Keep the top of the aquarium covered because Corys will suddenly swim to the surface to gulp air or eat. This will keep them from jumping out.
Diet: Scavenging omnivores; basic fish flakes, pellets, and bottom feeder tablets.
Notes: In large enough groups, Corys are schoolers and love to explore together. They are also bottom dwellers and might dig around looking for food, so have large unobstructed bottom areas with at least two inches of small smooth gravel or sandy substrate.
Kuhli Loaches (Species: Pangio kuhlii)
Size: 5 inches
Minimum Number: 3+ (non-schooling shoalers)
Minimum Aquarium Size: 10 gallons or 1:1 rule, whichever is greater.
Temperature: 75 to 86 °F (23.9 to 30 °C)
pH: 5.5 to 6.5
Setup Specifics: Keep the top of the aquarium covered because Kuhlis can escape. Since Kuhlis like to hide, provide caves and thick plant cover. They should have a lot of floor space to move around on, as this is where they will spend most of their time.
Diet: Mostly carnivorous, omnivorous bottom feeders: sinking pellets and flakes supplemented with live foods such as bloodworms, mosquito larvae, and brine shrimp.
Notes: Kuhli Loaches are active at night, but will be more active during the day if there is food scarcity or competition. Like all loaches, they are weather forecasting fish. This means they react upon atmospheric pressure changes. They become more active and even seemingly erratic. Avoid rocks with any sharp edges, as these will scratch and cause long term harm to their undersides. They prefer sand as a substrate, and they will sift and dig into it looking for food such as live bloodworms.
Bristlenose Plecos (Genus: Ancistrus)
Size: 5 inches
Minimum Number: 1 (see Notes)
Minimum Aquarium Size: 20 gallons
Temperature: 60 to 80 °F (15 to 27 °C)
pH: 5.5 to 7.6; juveniles are more sensitive to pH levels than adults.
Setup Specifics: Caves and other dark places to hide, such as under driftwood among plants, and larger smooth rocks and driftwood that provides space for algae to grow so they can graze.
Diet: Mostly herbivorous (85% plant matter and 15% protein); algae, raw vegetables (lightly boiled or microwaved to help them sink) such as zucchini, cucumber, squash, whole peas, and yams. Diet should be supplemented with sinking frozen food, such as daphnia or bloodworms, or live foods such as blackworms.
Notes: These fish eat a lot and thus produce a lot of waste. Count this fish as 4 inches per inch, therefore, a 5 inch Bristlenose Pleco needs at least a 20 gallon aquarium. Be prepared to use your gravel vacuum. It is not recommended to keep more than 1 male, or with any other similar shaped species, as they can be territorially aggressive toward each other. They are nocturnal, so they need plenty of dark hiding places. They will spend most of their time on the bottom, so ensure there is plenty of open space in this region. This species will occasionally dart to the surface for air, but if this begins to happen frequently, a water change may be in order, or the water might not be oxygenated enough, so considering an airstone is wise.
Harlequin Rasboras (Species: Trigonostigma heteromorpha)
Size: 2 inches
Minimum Number: 8+ (schooling)
Minimum Aquarium Size: 10 gallons or 1:1 rule, whichever is greater.
Temperature: 72 to 82 °F (22.2 to 27.8 °C)
pH: 6.0 to 6.5
Setup Specifics: Live plants such as the genus Cryptocoryne inhabit the harlequin rasbora’s native waters, but include open areas for schooling.
Diet: Omnivorous; flake food and freeze-dried bloodworms and tubifex, frozen and live foods.
Notes: Top to mid-dwelling, they will lay eggs on the undersides of broad-leaved plants.
Ember Tetras (Species: Hyphessobrycon amandae)
Size: 1 inch
Minimum Number: 8+ (ideally 8 to 10+ to form a large enough school to eliminate the remote possibility of them fin-nipping)
Minimum Aquarium Size: 10 gallons or 1:1 rule, whichever is greater.
Temperature: 73 to 84 °F (22.8 to 28.9 °C)
pH: 5.5 to 7.5
Setup Specifics: Soft sandy substrate, live plants.
Diet: Omnivorous but small mouthed; small-grained pellet or flake, and small live foods such as brine shrimp or daphnia.
Notes: Similar to bettas, ember tetras’ wild habitat is in slower waters, and so it doesn’t like fighting with fast water flow. Floating plants create shadowed areas which make the fish feel safe. Consequently, this may lead to a shiny orange red coloring of its body. Tetras are generally prone to some fin-nipping, but Ember Tetras are generally docile and more so in greater numbers.
Clown Plecos (Species: Panaqolus maccus)
Size: 4 inches
Minimum Number: 1
Minimum Aquarium Size: 20 gallons
Temperature: 73 to 82 °F (22.8 to 27.8 °C)
pH: 6.6 to 7.8
Setup Specifics: Caves and other dark places to hide in, such as under driftwood among plants; and larger smooth rocks and driftwood to provide space for algae to grow. Although clown plecos tend to rely less on algae than some other pleco species.
Diet: Omnivorous; they need driftwood to graze, and some algae, but also raw vegetables (lightly boiled or microwaved to help them sink) such as zucchini, cucumber, squash, whole peas, and yams; diet should be supplemented with sinking frozen food, such as daphnia or bloodworms, or live foods such as blackworms.
Notes: They eat a lot of driftwood and thus produce a lot of waste. Count this fish as 4 inches per inch, therefore, a 5 inch Clown Pleco needs at least a 20 gallon aquarium. Be prepared to use your gravel vacuum. It is not recommended to keep more than 1 male, or any other similar shaped species, as they can be territorially aggressive toward each other. They are nocturnal, so they need plenty of dark hiding places. They spend most of their time on the bottom so ensure there are plenty of open space regions.
Zebra Snails (Species: Neritina natalensis)
Size: 1 inch
Minimum Number: 1
Minimum Aquarium Size: 10 gallons or 1:1 rule, whichever is greater.
Temperate: 65 to 85 °F (18.3 to 29.4 °C)
pH: 6.5 to 8.5
Setup Specifics: N/A
Diet: Herbivorous; they will east algae from the glass and smooth rocks. If needed, supplement with algae wafers or raw or slightly boiled vegetables such as carrots and zucchini. Like all invertebrates, they also need calcium and other minerals for healthy shell development. This is accomplished by:
• Feeding them foods rich in calcium such as kale, spinach, and other leafy greens.
• Putting a cuttlebone in the water (in the filter is a good place unless you want them to graze on it directly, in which case boil it or soak it until it sinks).
• By using additives.
Notes: Do not use any food product, medication, or plant fertilizer that contains copper in any form, as copper is toxic to invertebrates. Commercial fish foods and medications may contain copper or copper sulfate. Always look at the ingredient list of any product you intend to put into your aquarium.
About author and webmaster… Troy Boylan
Ecoculture Village Founder & President, Anthropology BA, Interdisciplinary Studies: Ethnobotany BS. Two things I think are worth anything at all… all things wilderness and ecoculture… and well, RPGs… and skateboarding!
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